Based on MySQL 5.5.30, including all the bug fixes in it, Percona Server 5.5.30-30.2 is now the current stable release in the 5.5 series. All of Percona‘s software is open-source and free, all the details of the release can be found in the 5.5.30-30.2 milestone at Launchpad.

Percona Server.tar.gz binaries will now be shipped with the libjemalloc library. jemalloc package is now available in our apt/yum repositories as well. In case newer version is available in the distribution repositories that version will be used. Benchmark showing the impact of memory allocators on MySQL performance can be found in this blogpost. (Ignacio Nin)

This release of Percona Server has fixed a number of performance bugs. (Alexey Kopytov)

Drop table performance has been removed and its controlling variable innodb_lazy_drop_table has been deprecated. Feature has been removed because the upstream DROPTABLE implementation has been improved. (Laurynas Biveinis)

Due to parse error in the percona-server.specPercona Server rpm packages couldn’t be built on RHEL 5 and CentOS 5. Bug fixed #1144777 (Ignacio Nin).

When mysqldump was used with --innodb-optimize-keys option it produced invalid SQL for cases when there was an explicitly named foreign key constraint which implied an implicit secondary index with the same name. Fixed by detecting such cases and omitting the corresponding secondary keys from deferred key creation optimization. Bug fixed #1081016 (Alexey Kopytov).

Percona Server was built with YaSSL which could cause some of the programs that use it to crash. Fixed by building packages with OpenSSL support rather than the bundled YaSSL library. Bug fixed #1104977 (Ignacio Nin).

The log tracker thread was unaware of the situation when the oldest untracked log records are overwritten by the new log data. In some corner cases this could lead to assertion errors in the log parser or bad changed page data. Bug fixed #1108613 (Laurynas Biveinis).

Ported a fix from MariaDB for the upstream bug #63144. CREATETABLE or CREATETABLEIFNOTEXISTS statements on an existing table could wait on a metadata lock instead of failing or returning immediately if there is a transaction that executed a query which opened that table. Bug fixed #1127008 (Sergei Glushchenko).

Fix for bug #1070856 introduced a regression in Percona Server5.5.28-29.3 which could cause a server to hang when binary log is enabled. Bug fixed #1162085 (Alexey Kopytov).

Removed trx_list scan in read_view_open_now() which is another problem originally reported as upstream bug #49169. This also provides much better scalability in InnoDB high-concurrent workloads. Bugs fixed #1131189 (Alexey Kopytov).

In the event that a slave was disconnected from the master, under certain conditions, upon reconnect, it would report that it received a packet larger than the slave_max_allowed_packet variable. Bug fixed #1135097 (George Ormond Lorch III).

dialog.so used by the PAM Authentication Plugin couldn’t be loaded with Perl and Python clients when plugin-dir option was set in the [client] section of the my.cnf. Bug fixed #1155859 (Sergei Glushchenko).